Using spatial data mining method, this study analyzed parking violation cases from April to June in 2010, which were provided by 1999 citizen hotline of Taipei City Government, and tried to understand the locations of incidents and the trend. The results of Average Nearest Neighbor and Kernel Density Estimation revealed that parking violation cases did exhibit significant spatial dependence in Taipei City, and the areas with higher density of parking violation are included northern and western Zhongzheng, middle Songshan, northwestern Xinyi, and middle southern Da'an. In general, this study presented how Spatial Data mining can help the government to find the public opinion knowledge hidden in the data in order to further develop strategies and support policies.